Abstract:
:Spatial resolution in 3D breath-hold coronary MR angiography (MRA) is limited by imaging time. The purpose of this work was to investigate the feasibility of improving the spatial resolution of coronary MRA using generalized autocalibrating partially parallel acquisition (GRAPPA) and fast imaging with steady state precession (True-FISP) data acquisition. Coronary data were acquired in 10 healthy volunteers. In five volunteers, the data were fully acquired in k-space and decimated for GRAPPA with an outer reduction factor (ORF) of 2. The coil calibration in GRAPPA was improved by segmented least-squares fitting along the frequency-encoding direction. More than 5% of the total k-space lines were required for the calibration to achieve acceptable artifact suppression despite slightly lower signal-to-noise ratio (SNR). In another five volunteers, coronary data were obtained with both conventional and accelerated data acquisitions in the same imaging time. GRAPPA allowed a submillimeter in-plane resolution, and improved coronary artery definition with an acceptable loss of SNR. In conclusion, 3D breath-hold coronary MRA by GRAPPA and True-FISP is highly feasible.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Park J,McCarthy R,Li Ddoi
10.1002/mrm.20153subject
Has Abstractpub_date
2004-07-01 00:00:00pages
7-13issue
1eissn
0740-3194issn
1522-2594journal_volume
52pub_type
杂志文章abstract::Frequency-modulated (FM) pulses have practical advantages for spin-echo experiments, such as the ability to produce a broadband pi rotation, with an inhomogeneous radiofrequency (RF) field. However, such use leads to a nonlinear phase of the transverse magnetization, which is why FM pulses like the hyperbolic secant (...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21822
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abstract::Nuclear Overhauser effect (NOE) enhancements and relaxation times of 31P metabolites in human calf were measured in 12 volunteers (4 men and 8 women) at 1.5 T using a dual tuned four-ring birdcage. The NOE enhancements of inorganic phosphate (Pi), phosphocreatine (PCr), gamma-, alpha-, and beta-nucleoside triphosphate...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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journal_title:Magnetic resonance in medicine
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abstract::Levo-tetrahydropalmatine (l-THP) has shown significant promise in preclinical and clinical studies to treat drug addiction. Pharmacological MRI methods can elucidate the regional cerebral effects of l-THP, but there are potential confounds from the use of general anesthesia. To investigate the possible anesthetic-drug...
journal_title:Magnetic resonance in medicine
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abstract::The utility of a noninvasive steady state susceptibility-contrast MRI technique for continuous measurement of relative cerebral blood volume (rCBV) during global transient ischemia and subsequent hyperemia in a feline ischemia model is demonstrated. The measurements were obtained during a 10-min period of occlusion an...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2004-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2007-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2017-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910270107
更新日期:1992-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2007-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2016-01-01 00:00:00
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更新日期:2017-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2010-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21202
更新日期:2007-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/1522-2594(200101)45:1<167::aid-mrm1023>3.0
更新日期:2001-01-01 00:00:00
abstract:PURPOSE:To develop a method based on fat-water transition region extraction (TREE) for robust fat-water separation and quantification in challenging scenarios, including low signal-to-noise ratio (SNR), fast changing B0 field, and disjointed anatomies. THEORY AND METHODS:In TREE method, the phasor solutions of each pi...
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更新日期:2019-07-01 00:00:00
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更新日期:2018-04-01 00:00:00
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更新日期:1992-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1998-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2020-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2012-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1995-07-01 00:00:00
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更新日期:2015-08-01 00:00:00
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doi:10.1002/1522-2594(200007)44:1<41::aid-mrm8>3.0.co;
更新日期:2000-07-01 00:00:00